defense spending

Golden Dome: CBO Puts the Cost at $1.2 Trillion Over 20 Years While 97% of Next Year's Money Waits on Reconciliation

On September 29, 2026, Gen. Michael Guetlein told a Senate Armed Services subcommittee that an initial version of Golden Dome, the planned national missile defense system, could be ready by 2028, built from existing radars and interceptors. Six weeks earlier he had put it more bluntly to an audience in Huntsville: if the funding doesn’t come, there’s no Golden Dome.

Golden Dome is the defense program where the gap between ambition and money is widest. The President announced it in May 2025 at $175 billion, to be fully operational within about three years. Congress gave it $24.4 billion through the July 2025 reconciliation law. The rest depends on bills that haven’t passed.

A Ground-based Interceptor missile launches from Vandenberg Space Force Base during the FTG-12 missile defense test

Photo: U.S. Space Force, public domain via Wikimedia Commons

What it would cost

The program office estimates about $185 billion over ten years, through 2035. The Congressional Budget Office looked at a design capable of stopping ten intercontinental missiles in their boost phase and put the cost at about $1.2 trillion over twenty years, in 2026 dollars. Space-based interceptors make up about 70% of the acquisition cost. The constellation CBO modeled would need about 7,800 satellites and cost about $720 billion on its own.

Guetlein rejects CBO’s figure because it isn’t based on the program’s actual plans. CBO received its first classified briefing on the architecture only in late September. Outside estimates range even more widely, from about $250 billion to $3.6 trillion over twenty years.

What’s been bought so far

About 90% of the $24.4 billion from reconciliation had been committed by August 2026. In April the Space Force disclosed 20 agreements with 12 companies, worth up to $3.2 billion combined, to demonstrate space-based interceptors. The companies include Anduril, Lockheed Martin, Northrop Grumman, Raytheon and SpaceX. The demonstrations target 2028. In August all the providers passed the first of four milestones. Ground has been broken for the first operational site, at Joint Expeditionary Base Fort Story in Virginia.

The funding problem

The fiscal 2027 request for Golden Dome is $17.5 billion. Only about $398 million of that is in the regular defense budget. The other $17.1 billion, 97%, depends on a second defense reconciliation bill that hasn’t moved in either chamber. The House defense authorization bill authorizes $397 million.

Under the continuing resolution that funds the government to December 11, the program gets no new money. Guetlein has said he has no top line to fall back on.

Why the structure matters

Funding a multi-decade weapons system through one-off reconciliation bills is unusual. Reconciliation can pass the Senate with a simple majority, which makes it attractive when regular appropriations are stuck. It also means the money arrives in lumps, when a party has the votes, instead of the steady annual flow long programs need. Contractors can’t plan production lines around it.

Israel’s layered missile defenses, often cited as the model, were built over decades with steady annual funding, much of it from the US. Golden Dome is attempting something larger, faster, with money that arrives in irregular bursts. The 2028 target for an initial capability will test whether that can work.